Looking for additional NPF resources

[Charles Haincque <charleshaincque%gmail.com@localhost>]

Hello,

I am new to NetBSD (version 9.3) and I am starting to explore
configuring NPF. I have been reading the manual and looking at the
examples in /usr/share/examples/npf to create my npf.conf file.
However, I was wondering whether there are any additional resources
you would recommend to help me deepen my understanding and use of NPF?

Regards,
Charles